jev-nano
Tiny /v1/systemone-compatible decision server: a 7M-parameter CPU model in an 8 MB native binary, with conformal abstention.
Overview
jev-nano is described as the nano tier of local Jev: a /v1/systemone-compatible server answering noul, choice and score questions with probabilities, running a 7M-parameter model on any Linux x86_64 CPU from an 8 MB tarball. It is written in MFL, compiled through the machin C backend into a single static binary with no Python in the inference path. Any Jev or TypeSafe SDK client can point at it via base_url.
It uses a frozen trunk plus small trained heads with candidate log-probability scoring, and a calibrated conformal gate for abstention. The README reports 19 of 19 wire-contract checks passing and extra endpoints for routing with abstention, head lanes, chat completions and feedback. It is candid about quality: on JevBench's public set it scored 28% on the easy and original tiers (hard-tier states exceed its 384-token context), agreeing with hosted Jev on clear noul calls but near chance on fine-grained multi-way choices.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Yes / no | Does this convey urgency? | yes · no |
| Choice | Pick one option from the criteria map | — |
| Score | Place the state on the score legend | — |
How it works
- Install with the script and start the binary
- Point a Jev SDK client or curl at http://127.0.0.1:8097
- Send state and typed questions to /v1/systemone
- Get probabilities, or an abstention from the conformal gate
Strengths
- Runs on any CPU with an 8 MB download
- Drop-in /v1/systemone wire compatibility
- No Python or GPU needed
- Honest public benchmark results
Caveats
- Low accuracy on multi-way choices (28% on JevBench easy and original tiers)
- 384-token context limit
- Written in a niche language (MFL)
Getting started
curl -fsSL https://raw.githubusercontent.com/javimosch/jev-nano/main/install.sh | bash, then ./demo.shAt a glance
- Type
- Model
- Status
- prototype
- Language
- MFL
- Runtime
- Native binary HTTP server (Linux x86_64)
- Has code
- yes
- Has tests
- yes
Use cases and integrations
How curated lists describe it
The nano tier of local Jev — /v1/systemone-compatible typed decisions on a…
wh000wh000/awesome-jev-live
Frequently asked questions
Can I use the TypeSafe SDK with it?
Yes. Point the client's base_url at http://127.0.0.1:8097.
How accurate is it?
The README reports 28% on JevBench's easy and original tiers; fine on clear yes/no calls, near chance on multi-way choices.
Does it need a GPU or key?
No. It runs on CPU locally and needs no TypeSafe key.
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